Answer: $85,000
Step-by-step explanation:
Given : In a given population of two-earner male-female couples, male earnings have a mean of $40,000 per year and a standard deviation of $12,000.
Female earnings have a mean of $45,000 per year and a standard deviation of $18,000.
If C denote the combined earnings for a randomly selected couple.
Then, the mean of C will be :-
Hence, the mean of C = $85,000
Answer:
no Solution
Step-by-step explanation:
-12x-12y=4\\ 3x+3y=0
12x-12y=4
add 12y to both sides
12x-12y+12y=4+12y
divid both sides by -12
\frac{-12x}{-12}=\frac{4}{-12}+\frac{12y}{-12}
simplfy
x=-\frac{1+3y}{3}
\mathrm{Substitute\:}x=-\frac{1+3y}{3}
\begin{bmatrix}3\left(-\frac{1+3y}{3}\right)+3y=0\end{bmatrix}
\begin{bmatrix}-1=0\end{bmatrix}
Answer:
160 miles
Step-by-step explanation:
Let shirts be x and ties be y
3x+5y=$60 Equation 1 (Equation 1 will be denoted by *)
2x+3y=$39 Equation 2 (Equation 2 will be denoted by !)
*x2 6x + 10y = $120
!x3 6x + 9y = $117
*-! y = 120-117 =3
Ties are $3 each
Substitute this value back into one of the original 2 equations:
3x+5y=$60
3x+(5x3) = 60
3x+15=60
3x=45
x=15
Shirts are $15
